I had 2 SXX12 in a 4.5 cu ft box at 32hz ran off a t2000 birth-sheet rated at 2470rms at 1ohm. They hit pretty good, got low, sounded good, and hit pretty hard. But I dropped these after 2 months and went with 2 dc sounds lvl 4 same box and amp and the dc annihilates these re. but still not bad subs, you can do better for sure, but definitely do worse.